class_docstr: Rule class to handle processing
code: def outputs_set(self):
      return set(self.outputs or [])
  
imports: import ast
  from copy import deepcopy
  import hashlib
  import inspect
  import json
  from streamalert.shared.logger import get_logger
label_desc: Use image node_id 11 for calling the Rule obj's underlying member method code with example usage: obj.outputs_set() and returns: set